Oscillation-receiving device.



Gsw., PICKARD. OSCILLATION RECEIVING DEVICE.

APPLICATIN FILD DEC- Br 19|3- Ptentd A191120, 1915.

Atty transverselyI through A, B,

' reduce' or even y 1n' commercial telegraphy, 4 5

. Original application filed .Tuly 2t,

I GBEENLEAF WHITTIER PICK` i l CORPORATION OF IiTElllT YORK.,

naar ai' if;

n OF MESBRY, MASSACHUSETTSwASSIGNOR T0 WIRELESS SPECALTY APPARATUS COMPANY, OF BOSTON, MAS v saoHUsErrs, a'

*OSCILLTION-RECEIVING DEVICE.

risente.'

To all .uf/ 1,0192 t may concern PICKARD, a citizen of the United States of America, and a resident of Amesbury, Massachusetts, have invented certain new and useful Improvements in Oscillation-Receiving Devices, the principles of which are set forth in the following specification audaccompanying drawin Which discloses the form of the invention which I now consider toV be thebest of the various forms in which the principles of the invention maybe embodied. y This invention relates to Wireless telegra- 'phy detectors of the rectifier type, as now well known in the art, the object being to improve the, electrical, stability of the'device; and is also a division of my application foi patent Sferial Number 640,106, tiled 24th, 1911, and` relates particularly to the consists in employing, in the rectlfying substance,

, The invention cooperation with another substance 1n contact therewith which.

possesses peculiar properties which' result in very greatly improving the electrical stability ofthe device Ywhich include'sthe rectifyin r material. i

-\ Of the drawings,

section of an apparatus embodying the invention, and Fig. 2 is a vertical section taken Fig. 1.. instability has been a welltype of detector. in practice that Electrical known fault of the rectifier That is, it has been found electrical c urrentsor oscillations materially stronger than those of received signa-ls, and such as static or atmospheric, and even received signals themselves when the sender is in close proximity to the detector, tend to ytotally destroy the rectifying power of a detector in a given contact adj ustment. This, of course, is a serious thing l because it requires a new contact adjustment, which it may not be possible to obtain after a large part of the message has been lost.

'llhe present invention removes that fault by producing a combination which remains in operative adjustment under substantially all conditions which have previously caused instability.

' ll have found that the invention is best Specification ofl Letters Patent.

Judy

Figure 1 is a vertical PatentedApr. 20, 1915.. this application filed December ,8,

tact with thefrectlfying material, a( conductor which 1s characterized by .considerable brittleness, such that at all times there executed by employing as theisubstance` inv Y Be .1t known that I, GREENLEAF VVHlTTInR con 1s presented to the rectifying material a suit y ably small point of a rou h or unpollished surface resulting from the act that the brit? tle s ubstancebreaks oif by use instead of be` coming smooth or polished; Further than this present hypothesis, obscure why, class of materials makes the. duce electrical stability, but it seems to be due to the fact that a suitably small contact can alwaysjexist. Thefact is that all the materials which produce they desired result are characterized by extreme brittleness, and all of them l have found so far' are included in a peculiar new class` (brittle) of the materials classified by Mendeljeif in :his Wellknown period-lawftable- (However,..I do not Wish to be understood `as asserting that the brittleness,necessarily has any essential relation to the' operation.) Specifically the materials rnost useful Within the invention,

invention proare the following conductors, le, the'metn the reason is. as yet for a given adjustment, such seen that all these are comprised in 5. l The materials 4under the even-numbered i A series seem not so well adapte'd-forusein the inventiomalthough of course, l desire to include in the claims, all materials which are so adapted in greater or less degree. How ever, the materials which now se'em most useful under the invention, are included in said special class of Mendelejel"s group 5 and are characterized by extreme brittleness, as well as by other properties, among which are that there normally existsa tarnish or oxid coat ,on any exposed surface of these materials; and in use under the invention it is this tarnished surface which is used in Vcontact with the rectifying material, that to say, the surface becomes tarnished so quickly that notwithstanding the readiness of fracture, the fracture surface becomes assert that the tarnish has anything to do with the action of the device. The rectifyingmaterials which up to the resent time l. have found to be most useful y employed in combination with these brittle conductors is the element silicon, and particularly.Minen used with a substantially rough or unpolished, surface, such as an ordinary `fracture face', in contact with the brittle conductor such as bismuth, etc.

The drawings show a detector-holderof substantially the consti-notion shown in my prior Patent 912,726, dated February 16th, 1900. The rectifying material S, such as silicon, and the cooperating conductor A., such as bismuth, are held, preferably by soft readily fusible metal, in cups, one or both of the. cups being adjustable so that Contact selection may be had between S and A. J s shown, the silicon preferably has a rough surface presented to A. Likewise, the surface of the brittle conductor A which is presented to S, is rough, produced as by making e a fracture.

So far as I have determined as yet, the coperating contact members of this invention do not of themselves have the characteristic of rectifying, except as to such extent as may be due to the tarnish on their surfaces. Hence their function is substantially limited to that of furnishing a stable contact for the other or rectifying member; although it-vvould not be a departure from the invention to employ a material which also rectitied in dditionto executing the functions of the coperating contact members of the invention'. l f

Of course, thebmvention may be embodied in various mechanical forms, and by way of illustration,` reference is here made to another desirable form, which consists in employing one lof the brittle conductors, such as bismuth, as the sleeve 7 (or as a lower part -of such sleev') `f` Fig. 1 of my prior Patent 836,531, datedNbvember 20th, 1906. Pret'- erablya small mass of the bismuth is soldered or welded to the lower end of the sleeve 7 and the contact surface of the bismuth roughened as by making a fracture face.

The invention is not of course, limited to the elements bismuth, etc., but includes all materials which possess the properties of the same which are useful in the invention; und suchA materials may include conducting chemical compounds or alloys which possess such 4properties although the constituents thereof might lack such properties.

The expression rough surface in the claims implies, as stated above, that the operative portion is probably a single point effectively projecting from. such surface.

I claim:-

1. As a receiving device for wireless telegraphyA oscillations, the combination With a member containing silicon,` of a contacting member containing the metal bismuth.

2. As a receiving devlce for Wireless telegraphy oscillations,ithe combination with a* member consisting of the element silicon, of-

a contacting member consisting of the metal bismuth. l

3. As a receiving device for Wireless telegraphy oscillations, the combination with a silicon member, of a bismuth member having a rough surface in contact with said silicon member. v

4. As a receiving device for Wireless telegraphy oscillations, the combination with a silicon member having a rough surface, of a bismuth member in contact With such surface.

5. As a receiving device for Wireless telegraphy oscillations, the combination with silicon and bismuth members having rough surfaces respectively in contact with each other.

GREENLEAF WlH'lTIER PICKARD.

In presence of- 

